bloodsong, soulhuntre Just to clarify this, Firefly is based (supposedly) primarily on the REYES scanline rendering algorithm, which is noted for its high quality, speed and low resource usage. Ray tracing is a secondary function and should only be active when the renderer encounters a surface with raytracing materials. The specification for REYES renderers have been in the public domain for 15 years and it has been used as the primary rendering technique in most feature films since then. There are many REYES renderers available, including freeware implementations available and the technology is now extremely mature. The problem I and some others have with Firefly is that despite its alleged pedigree, it patently falls a long way short of REYES in terms of speed, quality and resource usage and far behind the quality of even relatively simple to implement (but slow) 'brute-force' ray tracing solutions. In short it seems to represent the worst of all worlds. This and the fact that that are some very clear 'quirks' (see my earlier post) as well as a lot unexpected aspects such as the use of polygon shading and smoothing, which are redundant in a renderer that implements micropolygon splitting and the extreme increase in memory usage relating to bucket size, raises genuine concerns that CL seriously dropped the ball on this one. Bill